Pinterest, a website geared toward finding common interests with other users and then “pinning” photos of them on individual pages, is quickly becoming an addictive social media site–much like Facebook and Twitter is to most users. Once you set up an account, you don’t have to be friends with someone to see what they’ve pinned; that’s part of the fun. You can find images of your dream house, a recipe you want to try out, or a cute craft idea to try with your kids. They all get pinned to their own category board on your page.

But some users find the site a little too distracting, as once you get started it’s hard to stop. And as reported earlier by Chris Richardson, some people are logging on just because their friends are and they want to join the novelty of it.

Another thing to consider when you start an account is that some of the images are copyrighted, as previously reported by Mike Fossum. User Kirsten Kowalski took down her pins for just that reason, claiming that the wording on the site regarding the copyright laws is confusing.

“Their lawyers say you can’t pin anything that you don’t own … but the site is saying you can. It’s very confusing to users,” Kowalski told Market Watch.

According to The New York Post, it is now the country’s 16th most visited website, ahead of major news sources CNN and The Huffington Post. Recently released infographics show the site’s stats and who the majority of the users are–mostly Facebookers–and after a good look at the website it’s easy to see why popularity has grown so exponentially; it’s easy to use, there are tons of colorful, well-photographed images to choose from, and the appeal of having all of one’s favorite things organized in one place is too much to pass over. It even surpassed Twitter in referrals last year, much to everyone’s surprise. And according to a blog post from Facebook, the number of their users logging on to Pinterest every day has increased by 60%.

While Pinterest‘s fan base is made up of mostly women, men are now starting to get in on the act of “pinning”, as well. The popularity of the social media site means copycat sites have begun to spring up around the web, including Gentlemint, which is geared directly toward men, and even one devoted to porn.

The company hasn’t yet released an API, but as reported by Chad Sweely, one is in the works, and it’s anticipated to be a huge cash cow for developers.